Review on Cryogenic and Jet Engine

Home , Cryogenic fuel, Cryogenic rocket engine, Jet engine, Reaction engine, Rocket engine nozzle

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

Abhishiktha Pagadala1, G Ritvik2, Lagumavarapu Venkata Guru Abhiram3

1,2,3Student, Dept. of Aerospace Engineering, Amrita School of Engineering, Tamil Nadu, India. ------***------Abstract - This paper gives an insight to the technology Jet engines are reaction engines. They are mainly used behind jet and cryogenic engines. A cryogenic engine uses to propel aircrafts. They draw air from the atmosphere, liquid fuel and oxidizer stored at extremely low temperatures increase its pressure by squeezing it and hence, use it for combustion, whereas a jet engine burns its fuel with the for the most required combustion reaction. The help of air sucked in from the atmosphere. This paper gives resulting hot gases are released from the nozzle of the an overview on how a cryogenic engine is different from a jet engine, providing enough thrust to the aircraft to move forward. engine. Also, the components and working of both cryogenic Jet aircrafts use turbojet engines which usually utilize engine and jet engine have been discussed. The liquid fuel and an afterburn, which is a second combustion chamber, oxidizer, when stored at extreme conditions, gives high placed between the turbine and the nozzle of the enthalpy of combustion on reaction, which makes it more engine. An afterburn elevates the temperature of the efficient when compared to jet engine. CE-20 is the first hot gases, thereby increasing the thrust of the aircraft indigenous cryogenic engine, which has proved to be highly by almost 40% during take-off and much higher during effective when used in GSLV MK-III. flight.

Key Words: Liquid fuel, oxidizer, cryogenic engine, jet 2. CRYOGENIC ENGINE VS JET ENGINE: engine. 2.1 Definitions 1.INTRODUCTION 2.1.1 Cryogenic Engine: Cryogenics is a branch of engineering that deals with Cryogenic engines are used in space launch the study of extremely low temperatures, behavior of vehicles, in the last stage of a rocket. A Cryogenic different materials at these temperatures and their engine uses both cryogenic fuel and oxidizer, liquefied production. at a very low temperature.

Temperature range of 123 Kelvin (-150° Celsius) to absolute zero (-273° Celsius) has been defined as cryogenic temperature range.

Materials at cryogenic temperatures are nearly static and in an ordered fashion.

A rocket engine that uses cryogenic fuel and oxidizer for its operation is called a cryogenic engine. The fuel and oxidizer used in a cryogenic engine are liquefied gases, stored at extremely low temperatures. Generally liquid hydrogen liquefied at -253° Celsius is used as fuel and liquid oxygen liquefied at -183° Celsius is used Fig - 1 : RS-25 Engine as oxidizer. Several fuel-oxidizer combinations have been used, but hydrogen-oxygen combination was 2.1.2 Jet engine: found to the best as they are easily available, Jet engine, also known as a reaction engine, produces a economical and have very high enthalpy of combustion. fast-moving jet, which generates a thrust, for the aircraft to move forward. Few typical examples of jet

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072 engines are: turbojet, ramjet, pulse jet, turboprop, The fuel and oxidizer which are stored as turboshaft and turbofan. liquids, evaporate as they get injected into the thrust chamber and they undergo combustion. The products of combustion, which is a mixture of hot gases, are allowed to expand through the exhaust nozzle and the resulting high velocity jet produces the propulsive thrust.

2.3.2 Jet engine: Jet engines are similar to gas turbines, the working principle is one and the same for both. A jet engine sucks air into the engine by means of its fan. The air is made to pass through a

Fig- 2 : Jet Engine compressor, which increases its pressure by compressing it. This pressurized air, enters the  The working principle of cryogenic and jet combustion chamber, where fuel is diffused. engines is same, the thrust is produced by an The mixture of fuel and air is ignited by means internal combustion/pressure difference; this of an electric spark. As a result of the follows Newton’s Third law of motion- “Every combustion reaction between the air and fuel, action has an equal and an opposite reaction”. the gases burn and blast out through the nozzle present at the rear of the engine, providing the  The jet engine gets the required oxygen from required thrust for the aircraft.

air to burn the fuel, whereas rockets carry their 2.4 Efficiency: oxidizer, to operate in space.

2.4.1 Cryogenic engine:  Intake and exhaust are two passages present in The efficiency of a cryogenic engine is much a jet engine, whereas a cryogenic engine has higher than that of a jet engine. It is very cost- only one passage for exhaust. effective. 2.2 Parts Cryogenic engine uses liquid hydrogen as fuel and liquid oxygen as the oxidizer. Parts of cryogenic engine are: It produces more thrust and generates enough 1. Combustion/Thrust chamber. power. This means the engine runs for a 2. Fuel injector. greater distance using less amount of fuel. 3. Turbo pumps 4. Gas Generator 2.4.2 Jet engine: 5. Cryogenic valves The efficiency of a Jet engine or air-breathing 6. Regulators engine is quite low as compared to cryogenic 7. Tanks engines. 8. Rocket engine nozzle The formula for the efficiency of an air breathing engine is- Parts of jet engine are: 1. Fan ηp = 2 (ve / v) /1+( ve / v)2 2. Compressor where, 3. Combustor v - Velocity of engine 4. Turbine. ve - Exhaust velocity 5. Exhaust nozzle η p – Propulsive Efficiency

2.3 Working Jet engines are said to be more efficient at higher altitude due to the fact that the air at 2.3.1 Cryogenic engine: that level is much colder and less dense, which A cryogenic rocket engine works on the basis of minimizes the amount of fuel burnt. Jet engines thrust produced by high velocity exhaust jet. © 2021, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 2595

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

provide high velocity to the aircraft as they of thrust is provided. In a cryogenic engine fuel increase the density of air inside the engine injector is usually in the shape of a disc, which followed by a combustion reaction. This is perforated, and is present right above the increases the pressure, which in turn results in combustion chamber. higher forward thrust. 2.5.3 TURBO PUMPS: Table 1: Differences between cryogenic and jet Turbo pumps are used to deliver liquid oxygen engines and liquid fuel to the combustion chamber form the oxygen tank and fuel tank Cryogenic engines Jet engines respectively, at very low temperatures. No air intake is required in this Air intake is required to engine. operate this engine. 2.5.4 GAS GENERATOR: The temperature of fuel must be Fuel storage does not require For the fuel and the oxidizer to flow through very low. low temperature. the turbo pumps to reach the combustion It runs efficiently when low It runs efficiently at temperature fuel transforms and supersonic speed that chamber, some force is required. This force is mixes correctly and ignites. forcefully compress air before provided by gravity when the rocket is on the combustion. launch pad, and during the time of flight, the upward acceleration of the rocket, provides the necessary downward force. However, these 2.5 PARTS AND WORKING OF CRYOGENIC ENGINE: forces do not provide enough pressure. Therefore, a gas generator is used. Gas 2.5.1 COMBUSTION CHAMBER/THRUST generator, provides the sufficient amount of CHAMBER: gas which acts as a driving force to push the A combustion chamber is the heart of a rocket fuel through the pumps into the combustion engine. Fuel and oxidizers which are stored at chamber, during its operation. their respective tanks are pumped through the 2.5.5 CRYO VALVES: turbo pumps into the combustion chamber. On Cryogenic valves or cryo-valves are used to combustion, they get ignited. As a result of store or transport liquefied gases at very low combustion between these condensed-phased temperatures. They control the flow of fuel and propellants at high pressure, massive amounts oxidizer. of hot gases are released from the nozzle,

where the flow accelerated. 2.5.6 REGULATORS: A cryogenic engine uses liquid hydrogen With the help of pressure regulators, liquefied liquefied at 20 Kelvin as fuel, and liquid oxygen, gases can be stored at constant pressure liquefied at 90 Kelvin as oxidizer. Several fuel- inexpensively, during the time of operation. oxidizer combinations have been used, but

hydrogen-oxygen combination was found to be 2.5.7 TANKS: the best as they are easily available, economical The cryogenic fuel and the oxidizer are stored and have very high enthalpy of combustion. at extremely low temperatures, in two different 2.5.2 FUEL INJECTOR: tanks called fuel tank and oxidizer tank Fuel injector in a cryogenic engine is respectively. responsible for the flow rate and the intermixing of fuel and oxidizer, as they are 2.5.8 ENGINE NOZZLE: injected into the combustion chamber. It The engine nozzle expands and accelerates the atomizes the liquid fuel and mixes it with the hot gases produced as a result of combustion in oxidizer in order to achieve rapid and complete the thrust chamber, so that the gases exit the combustion as a result of which, a huge amount

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

nozzle at hypersonic speeds, providing the rocket enough thrust.

The key objective of a rocket’s propulsion system, which includes all the parts that make up the rockets engine, is to provide enough thrust to the rocket, by ejecting high speed mass of gases through the nozzle, giving it enough reaction force to move upward.

Rocket engines follow the Newton’s Third Law of Motion i.e. “For every action there is an equal and an opposite reaction.” Rocket engine operates by the thrust which is given by the engines due to burning of fuel. Such an immense amount of energy for a short time creates enough impulse to provides thrust for lift-off.

The liquid fuel and oxidizer stored in their respective tanks is pushed into the combustion Fig- 3 : Rocket Engine chamber, by means of the gas generator, to initiate the process of combustion. On reaching 2.4 PARTS AND WORKING OF JET ENGINE the combustion chamber, the fuel and oxidizer mix with each other, releasing a huge amount 2.4.1 INTAKE: of hot gases through the nozzle. As a result, the Intake of a jet engine is the passage that guides in the rocket moves upward. atmospheric air and provides it to the fan/compressor

at the required velocity and pressure. FThrust = v(dm/dt) Where, dm/dt is rate of change of mass of 2.4.2 1FAN: combustion product. The first part of the turbofan or the turbojet engine, is the fan. This huge spinning fan sucks in large quantities of air, increases its velocity and splits it into two parts. The first part of the air passes through the core of the engine, where the other components of the engine act upon it. Whereas the second part flows through the duct that surrounds the core to the rear of the engine. The advantage of having a bypass system of this kind is that it provides additional thrust to the aircraft.

1Fan is used only in turbojet and turbofan engines.

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

2.4.3 COMPRESSOR: These hot exhaust gases along with the cold air exit the engine through exhaust nozzle. The compressor is the first component of the engine’s core. The main role of a compressor is to increase the pressure of the air, which is done by squeezing the air and forcing it into the combustion chamber.

2.4.4 COMBUSTOR:

The third part of a jet engine is the combustor. Here, fuel is sprayed into the airstream which causes ignition Fig- 4 : Jet Engine resulting in a high temperature and high energy airflow. 3. WHAT MAKES CRYOGENIC ENGINE EFFICIENT? 2.4.5 TURBINE: In space shuttles, cryogenic engines have been one of The turbine of the engine is connected to a shaft, which the most efficient rocket engines. In cryogenic engines, is connected to the fan in the front part of the engine. It Liquid Oxygen (LOX) is used as oxidizer and Liquid receives the high energy airflow produced by the Hydrogen (LH2) is used as fuel. Super cooling is done in combustor which causes the blades of the turbine to order to have a high mass flow rate, which in turn rotate. As the turbine rotates the fan also starts to increases rocket efficiency. On ignition, at a rotate. temperature of about 873 Kelvin, hydrogen fuel reacts with oxygen in a highly exothermic fashion to give 2.4.6 EXHAUST NOZZLE: more than 200 kilojoules per mole of energy along with an enormous amount of steam. The exhaust nozzle produces the require forward thrust for the aircraft. The energy drained airflow that 2 H2(g) + O2(g) → 2 H2O(g)+ High Energy passes through the turbine passes through a mixer, where this high-temperature air is mixed with the low- Such an immense amount of energy from a 2 m wide temperature air that bypasses the fan. The exhausted exhaust results in upward thrust of the rocket by the air produces a force, propelling the aircraft forward. superheated steam with enough velocity out of the atmosphere. Air is sucked into the jet engine by the turbo fan at the front, and passes through the inlet.

The compressor of the engine squeezes the air by eight times, and increases the pressure. This dramatically increases its temperature.

The mixture of fuel and air gets ignited in the combustion chamber. As a result, hot gases are produced which increases the temperature to around 900°C. Chart - 1 : Propulsive Efficiency Curve

The exhaust gases pass through the blades of the Liquid Hydrogen is used as a fuel and Liquid Oxygen, turbine. As the turbine gains energy, it spins. which is an oxidizer, is used to oxidize with the Liquid Hydrogen to give out a high amount of energy. Pure A shaft connects the turbine and the fan. As the blades liquid oxygen used as an oxidizer at high temperature, of the turbine spin, the fan starts to run. i.e., in the range of 500 to 600°C, on reaction with © 2021, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 2598

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

Liquid Hydrogen, releases huge amount of energy CE-20 is the first cryogenic engine developed by ISRO’s fluxes, unmatchable to any present-day jet engines. liquid propulsion system center, to facilitate the upper stage of the geostationary satellite launch vehicle 4. INDIA’S FIRST CRYOGENIC ENGINE (GSLV). It has an immense potential to produce an Indian researchers are mainly responsible for the upward thrust of 186.36 kilonewton along with a innovation of cryogenic engines, which in turn, has specific impulse of 444 seconds. provided our researchers a greater hold in rocket motors. GSLV MK III, facilitated with the cryogenic engine has proved effective, which implies ISRO can manufacture and dispatch their satellites independently.

The Indians were able to make an indigenous cryogenic engine, thanks to the Russians under Mikhail Gorbachev, Glavkosmos, the space agency of USSR.

Unlike USSR, the US, Europe, Japan and China were against to share their expertise in cryogenic technology. USSR and India said cryogenic technology Fig - 5: CE 20 would be used only for weather and communication satellites and will not be used for military purposes. 5. CONCLUSION The US did not have trust them. To impose sanctions on Indian and Soviet space agencies, they invoked the A cryogenic engine imparts very high specific impulse, Missile Technology Control Regime (MTCR) in 1991. making it suitable for using it in a rocket’s upper stage. In 1993, when Yeltsin’s government came to power, The jet engine involves a bypass system. The air which Yeltsin met Bill Clinton in the US and came to a enters the engine splits to two parts. One part passes compromise with the MTCR that they would not through the core of the engine, while the other moves transfer the technology to ISRO, instead will sell all the towards the rear of the engine. Such bypass system seven cryogenic engines. increases the thrust provided to the aircraft. Whereas India decided to fight back with making a cryogenic in cryogenic engines, the release of huge amount of technology of its own. After a lot of attempts, in gases, which are combustion products, are enough to December 2003, ISRO had ground tested three engines provide the upward thrust to the rocket. However, the for about 90 minutes. One of those engines was fired efficiency of a cryogenic engine is very high when for more than 16 minutes continuously, which is four compared to that of a jet engine. minutes longer than the time for which it would be REFERENCES fired during flight. [1]https://www.britannica.com/science/matter In April 2010, GSLV D-3 with a GSAT-4 was the first flight, installed with an indigenous cryogenic engine. [2]https://blogs.nasa.gov/J2X/tag/cryogenic- But it failed to run 3 seconds after its launch. propellants

After the challenging task of engine operation and [3]https://blogs.nasa.gov/Rocketology/tag/liquid- ignition testing under vacuum conditions, GSLV’s fifth hydrogen-ROCKETOLOGY:NASA’s developmental flight carrying the GSAT-14 satellite [4]https://economictimes.indiatimes.com/definition/c was launched from Sriharikota with the indigenously ryogenic-engine developed CUS-05 engine. [5]https://www.explainthatstuff.com/jetengine.html © 2021, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 2599

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

[6]https://www.grc.nasa.gov/www/k- [22] https://i.stack.imgur.com/qRTQR.gif 12/UEET/StudentSite/engines.html [23]https://upload.wikimedia.org/wikipedia/common [7]https://howthingsfly.si.edu/ask-an- s/4/4c/Jet_engine.svg explainer/what%E2%80%99s-difference-between-jetengine-and-rocket-engine [25] https://gumlet.assettype.com/swarajya/2019- 07/5ee43bef-0c9f-42f6-bacf- [8]https://www.highskyflying.com/why-are-jet- d408d4324ace/10_6c25cryogenicstageatstagepreparat engines-more-efficient-at-higher-altitudes/ ionfacility.jpg?w=1200&h=798

[9]https://www.thehindu.com/opinion/lead/The- [26] Wikipedia long-road-to-cryogenic- technology/article14691425.ece BIOGRAPHIES “Abhishiktha Pagadala is an 18- [10]http://www.ijmerr.com/v2n4/ijmerr_v2n4_44.pdf year-old from Hyderabad. She -CRYOGENIC completed her entire schooling from Sanskriti School, Kondapur, [11]https://www.isro.gov.in/gslv-d5-gsat- Hyderabad. She is a very 14/indigenous-cryogenic-engine-and-stage enthusiastic and confident individual who has taken part in [12]https://www.isro.gov.in/update/12-oct- various leadership and social 2018/isro-successfully-tests-cryogenic-engine-ce-20- activities during her schooling. She gslv-mk-iii-chandrayaan-2-mission was an active participant in various national level competitions [13]https://www.jagranjosh.com/general- and conferences. She is currently pursuing bachelor’s degree in knowledge/what-is-cryogenic-technology-know- Aerospace Engineering in Amrita about-isros-biggest-cryogenic-propellant-tank-from- Vishwa Vidyapeetham, hal-1606825719- Coimbatore. She plans to pursue 1#:~:text=India%20decided%20to%20fight%20back,f her Masters in the same field.” light%20was%20conducted%20in%202014. “G Ritvik is an 18-year-old from [14]https://link.springer.com/book/10.1007/978-3- Hyderabad He finished his 642-10565-4 schooling from The Creek Planet School, Bachupally, Hyderabad and [15]https://www.nasa.gov/feature/glenn/2021/small graduated high school from er-is-better-for-jet-engines FIITJEE, Miyapur, Hyderabad. He is a very determined, dedicated and a [16]https://www.pilotmall.com/blogs/news/turbopro creative individual and has a p-vs-jet-learn-their-advantages-and-disadvantages passion for graphic designing. He has been a part of many national [17]https://www.quora.com/What-is-the-difference- level events and competitions. He between-a-cryogenic-engine-and-a-scramjet is currently pursuing his bachelor’s degree in Aerospace Engineering [18]https://science.thewire.in/spaceflight/gslv-mk-3- in Amrita Vishwa Vidyapeetham, cryogenic-engine-operational-flight-chandrayaan-2/ Coimbatore. He plans pursue a career in the same field.” [19]https://www.vssc.gov.in/VSSC/index.php/launche rs/gslv “LVG Abhiram is an 18-year-old from Hyderabad. He finished his [20]https://en.wikipedia.org/wiki/File:Shuttle_Main_E schooling from St. Joseph Public ngine_Test_Firing.jpg School, Malakpet, Hyderabad and graduated high school from [21]https://en.wikipedia.org/wiki/File:F100_F- FIITJEE, Dilshuknagar, Hyderabad. 15_engine.JPG As a hardworking and passionate individual, he has taken part in various National and International © 2021, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 2600

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 08 Issue: 07 | July 2021 www.irjet.net p-ISSN: 2395-0072

level Olympiads and quizzes in Math and Sciences. He is competitive in nature. He is currently pursuing his bachelors in Amrita Vishwa Vidhyapeetham, Coimbatore. He aspires to pursue his higher studies in astrophysics.”